The tumor-promoting effects of PTGS2 have been attributed to its ability to induce signaling pathways downstream of RAS (73), PI3K/AKT (72), and ERK (70)
The tumor-promoting effects of PTGS2 have been attributed to its ability to induce signaling pathways downstream of RAS (73), PI3K/AKT (72), and ERK (70). and conferred sensitivity to immunotherapy. Mechanistically, we found that these effects were mediated through EPHA2/TGF-/SMAD axisCdependent activation of prostaglandin endoperoxide synthase 2 (transcript large quantity in The Malignancy Genome Atlas (TCGA) data set (Physique 1A). Pathway analysis of this group of genes indicated activation of EPH/ephrin signaling as one of the top 5 gene signatures associated with the T cellCnoninflamed phenotype (Supplemental Physique 1A and Physique 1B) and identified as the most highly expressed EPH family member in human G007-LK PDA (Physique 1C). EPH proteins are a highly conserved family of receptor tyrosine kinases that function in development, particularly in neurogenesis and angiogenesis, and regulate a pleiotropic set of cellular functions. EPHA2 is usually overexpressed G007-LK in multiple tumor types, and its expression correlates with poor prognosis and therapy resistance (25). Importantly, the mRNA expression level of negatively correlated with but not expression was inversely correlated with patient survival (Physique 1E), consistent with previous studies showing that a high large quantity of tumor-infiltrating T cells is usually associated with survival in human PDA (26C28). These results suggest that expression inversely correlates with T cell infiltration in human PDA and may G007-LK have clinical significance. Open in a separate window Physique 1 Expression of correlates with the large quantity of CD8+ T cells in PDA.(A) Pipeline for identification of signaling pathways negatively associated with the abundance of transcripts in the TCGA PDA data set. (B) EPH-ephrin signaling pathways inversely correlated with transcript large quantity in TCGA PDA data set. (C) The transcript G007-LK large quantity of EPH receptor family members in human PDA data set from TCGA. (D) Correlation of transcript large quantity for and in human PDA samples from TCGA (left). Large quantity of transcript in the top and bottom 20% of expression (middle), and transcript large quantity in top and bottom 20% of expression (right) in human PDA samples from TCGA. (E) Kaplan-Meier survival curves generated from TCGA PDA data set; upper and lower deciles of expression offered (= 17/group). (F) The transcript large quantity of EPH receptor family members in mouse PDA cells (= 7/group). (G) The mRNA expression levels of in YFP+ tumor cells and YFPC stromal cells from subcutaneously implanted KPCY tumors (= 20/group). (H) The mRNA expression levels of in YFP+ tumor cells from subcutaneously implanted mouse T cellChigh and T cellClow KPCY tumors (= 10/group). (I) The surface protein levels of Epha2 in YFP+ tumor cells from subcutaneously implanted T cellChigh and T cellClow KPCY tumors (= 10/group). (C, D, FCI) Data are offered as box plots; each sign represents a single patient or mouse tumor sample, and each box represents a group with horizontal lines and error bars indicating imply and range, respectively. Statistical analysis by Students unpaired test (D, GCI) or 1-way ANOVA with Tukeys HSD post test (C and F). *** 0.001; **** 0.0001. We recently reported a library of congenic pancreatic tumor cell clones that faithfully recapitulate the heterogeneity of immune cell infiltration in PDA (8). Specifically, clones fell into 2 groups: T cellChigh tumor cell clones, which generate implanted tumors with tumor-infiltrating T cells and a paucity of suppressive myeloid cells, and T cellClow tumor cell clones, which generate tumors with the opposite representation of immune cells (Supplemental Physique 1D). In this experimental system, was again the top expressed gene in the family (Physique 1F), and it was Thymosin 4 Acetate expressed predominantly in tumor cells (marked by yellow fluorescent protein [YFP]) as compared with YFP-negative nontumor cells (Physique 1G). Moreover, mRNA and the proportion of EPHA2+ cells were higher in subcutaneous tumors derived from T cellClow tumor cells versus T cellChigh tumor cells (Physique 1, H and I). Based on this strong correlation between EPHA2 expression and a paucity of tumor-infiltrating CD8+ cells in both murine and human PDA, we hypothesized that EPHA2, expressed by malignancy cells, regulates immune infiltration in pancreatic malignancy. Tumor cellCintrinsic Epha2 regulates T cell infiltration and sensitivity to immunotherapy. To test this hypothesis, we investigated the effect of deletion around the TME using our congenic mouse PDA tumor cell clones. Utilizing the CRIPSR-Cas9 technique, we generated ablation in these clones resulted in a significant increase in CD3+ T cells in subcutaneously implanted tumors, both in terms of absolute numbers and as a percentage of CD45+ cells (Physique 2, ACC). Flow analysis showed.